1. An engine has been compression tested. The number two cylinder is below specifications. After injecting oil, the pressure does not increase. The engine has:
A. A faulty head gasket.
B. A bad valve.
C. Worn piston rings.
D. A hole in the piston.
Answer B is correct. This second compression test designed to increase compression by increasing the seal between the rings and the cylinder wall is called a wet compression test. If there is little or no change in compression after adding oil, the engine has a bad valve, typically an exhaust valve.
During the initial inspection of an engine, the technician notices that the oil filter has swollen larger than normal. All of the following will result in this condition EXCEPT:
A. Contaminated oil.
B. Stuck closed oil pressure relief valve.
C. Stuck closed oil filter bypass valve.
D. Worn main crankshaft bearings.
Answer D is correct. Each of these conditions would result in a ballooned oil filter except main bearings. Worn engine bearings and faulty oil pumps result in low oil pressure.
One valve tip on a cylinder head is much higher than the others. The MOST likely cause of this is:
A. Weak spring tension.
B. Valve spring installed height.
C. The valve seat.
D. Loose head bolts.
Answer C is correct. A worn valve face or seat is the most likely cause. Measure the valve stem installed height if one tip is higher than the others.
The measuring tool illustrated above is a:
A. Dial indicator for measuring crankshaft rod journals.
B. Micrometer for measuring crankshaft rod journals.
C. Dial indicator for measuring crankshaft endplay.
D. Bore gauge for measuring cylinder wall thickness.
Answer C is correct. A dial gauge is used to measure end-play clearance.
A V-8 engine with a liquid cooled supercharger is detonating during acceleration. Technician A says to inspect the intercooler's radiator for debris. Technician B says a special adapter may be required to pressure test the system. Who is correct?
A. Technician A
B. Technician B
C. Both A and B
D. Neither A or B
Answer C is correct. Superchargers require an intercooler to cool the heated compessed air charge before entering the air inlet. This cooled air prevents harmful detonation.
6. A spark plug has a square electrode and the tip is light gray colored. Which of the following is correct about this spark plug reading?
A. The piston rings are worn.
B. The fuel injector is leaking.
C. The engine has a bad valve.
D. This reading shows normal wear.
Answer D is correct. A light tan or light gray colored spark plug tip is considered normal. Today’s fuel injected engines usually turn the tip a light gray color. The center electrode should be square, not rounded; this is because spark readily jumps off a square edge.
While removing the spark plugs from an engine, it is noticed that one spark plug's ceramic insulator is shorter than the others. Technician A says that the shorter spark plug has a different heat range than the other plugs. Technician B says a cold spark plug with too low of a heat range for that engine may foul prematurely. Who is correct?
A. Technician A
B. Technician B
C. Both A and B
D. Neither A or B
Answer C is correct. A hot spark plug self cleans better than a cold plug, but a cold plug is better at preventing pre-ignition. Pre-ignition occurs when the air/fuel charge has burned too soon, and detonation occurs when the air/fuel charge burns too fast. Manufacturers' spend a great deal of time choosing the right spark plug for their engine.
A light duty truck with a five-speed manual transmission has a rattling noise at the back of the engine that increases with engine speed. Technician A says the flywheel bolts may be loose. Technician B says to torque flywheel bolts in a crisscross pattern according to the manufacturer's specifications. Who is correct?
A. Technician A
B. Technician B
C. Both A and B
D. Neither A or B
Answer C is correct. Loose flywheel or flexplate bolts make a rattling sound heard toward the rear of the engine where it's joined to the transmission's bellhousing.
The oil pressure warning light stays illuminated whenever the engine is running. The oil pressure is within specifications. Technician A says the oil pressure switch may be faulty. Technician B says to test the oil pressure switch with an ohmmeter. Who is correct?
A. Technician A
B. Technician B
C. Both A and B
D. Neither A or B
Answer C is correct. They are often normally closed switches; this is why the oil pressure warning light illuminates when the ignition is first turned on and goes out after the engine starts and oil pressure rises.
During a cylinder leakage test, a hissing sound is heard coming from the tailpipe. Technician A says a faulty intake valve will cause this test result. Technician B says a leaking head gasket will cause this sound at the tailpipe. Who is correct?
A. Technician A
B. Technician B
C. Both A and B
D. Neither A or B
Answer D is correct. A hissing sound from the tailpipe indicates a leaking exhaust valve or seat. The exhaust valve leads to the exhaust manifold /tailpipe.
After diagnosing and replacing the cooling system's water pump, the vehicle's engine continues to overheat. Which of these is the MOST likely cause?
A. An air pocket in the system.
B. Leaking head gasket.
C. Faulty replacement water pump.
D. The radiator.
Answer A is correct. Air pockets occur after draining the engine's coolant. Some vehicle's are more prone to this problem than others.
Two technicians are discussing engine sealants and form in place gaskets. Technician A says sealants such as RTV are aerobic. Technician B says some sensors may be damaged if an unapproved sealant is used. Who is correct?
A. Technician A
B. Technician B
C. Both A and B
D. Neither A or B
Answer C is correct. Anaerobic sealers are usually used on smooth, machined components. They dry in the absence of air.
An engine has a noise that goes away as the engine warms and reaches operating temperature. Which of these is the MOST likely cause?
A. Loose main bolt.
B. Loose connecting rod bolt. C. Piston to wall clearance.
D. Loose intake manifold.
Answer C is correct. As the piston expands, the clearance between it and the cylinder wall decreases, and so does the noise known as piston slap.
An engine suffers from detonation. Technician A this may be caused from a defective EGR valve. Technician B says advanced ignition timing can cause this condition. Who is correct?
A. Technician A
B. Technician B
C. Both A and B
D. Neither A or B
Answer C is correct. A stuck closed EGR valve will cause ping (detonation) while a stuck open valve will cause an engine to stumble and stall.
Technician A says faulty turbocharger bearings will result in a loss of engine oil. Technician B says a dirty turbocharger air filter will result in a loss of engine oil. Who is correct?
A. Technician A
B. Technician B
C. Both A and B
D. Neither A or B
Answer A is correct. Faulty turbocharger bearings will result in oil seal failure.
A squeal is heard in the front of a supercharged V6 engine. This squeal gets louder as the engine is accelerated. Which of these is causing this condition?
A. Supercharger front roller bearings.
B. Faulty serpentine belt tensioner.
C. Turbine shaft needle bearings.
D. Both A and B
Answer D is correct. Superchargers are belt driven and contain bearings that will squeal when worn or deprived of lubricant.
A vehicle's engine is sluggish and slow to crank. Technician A says to check the starter and its circuit first. Technician B says to check the voltage, capacity, and condition of the battery. Who is correct?
A. Technician A
B. Technician B
C. Both A and B
Answer B is correct. Always inspect and test the battery and its connections first.
A vehicle’s battery is good and passes all testing, but continues to die overnight. It’s being tested for parasitic battery drain. Technician A says to set the meter to measure voltage and connect the probes in series between the positive terminal and the battery post. Technician B says to set the meter to measure amperage and connect the probes in series between the negative battery terminal and the negative battery post. Who is correct?
A. Technician A
B. Technician B
C. Both A and B
D. Neither A or B
Answer B is correct. Technician B is correct. Set the meter to measure amperage and connect the probes in series between the negative battery terminal and the negative battery post.
Two technicians are discussing cylinder bore measurements. Technician A says the cylinder's bore should be measured for out of round. Technician B says the cylinder's bore should be measured and checked for taper. Who is correct?
A. Technician A
B. Technician B
C. Both A and B
D. Neither A or B
Answer C is correct. Both technicians are correct.
Technician A says that connecting rods and the rod caps are matched and can not be mixed. Technician B says it may be necessary to mark these parts for reassembly. Who is correct?
A. Technician A
B. Technician B
C. Both A and B
D. Neither A or B
Answer C is correct. This is true, it is a good idea to help avoid a mix up, but never mark the arm or beam as this can create a weak point and eventual engine failure. Mark the base, only if necessary.
Engine crack repair is being discussed. Technician A says metal pinning is an accepted method of cracked cylinder head repair. Technician B says metal pinning is an accepted method of cracked engine block repair. Who is correct?
A. Technician A
B. Technician B
C. Both A and B
D. Neither A or B
Answer C is correct. Metal pinning is an acceptable method for repairing a cracked cylinder head or an engine block.
Which of these is LEAST likely to cause low oil pressure in an engine?
A. A faulty oil pressure valve.
B. Worn crankshaft bearings.
C. Worn camshaft bearings.
D. Worn valve guides.
Answer D is correct. This is the least likely. It is unlikely that a valve guide will lower oil pressure.
Technician A says valve spring installed height is measured from the outer edge of the valve spring retainer to the pocket in the cylinder head. Technician B says that too thin of a valve margin will not effect its operating temperature. Who is correct?
A. Technician A
B. Technician B
C. Both A and B
D. Neither A or B
Answer A is correct. Valve spring installed height is measured from the outer edge of the valve spring retainer to the pocket in the cylinder head.
Technician A says that magnetic particle detection is an acceptable method for detecting cracks in aluminum castings. Technician B says a special dye is used to detect cracks in aluminum castings. Who is correct?
A. Technician A
B. Technician B
C. Both A and B
D. Neither A or B
Answer B is correct. A special dye is used to inspect for cracks in aluminum.
Technician A says that minor scoring on the surface of a flywheel can be removed. Technician B says if the transmission flexplate's ring gear shows excessive wear or cracking it must be replaced. Who is correct?
A. Technician A
B. Technician B
C. Both A and B
D. Neither A or B
Answer C is correct. Scoring on the surface of a flywheel can be removed by resurfacing. The ring gear can be replaced making it reusable. A cracked flexplate is always replaced with a new one.
Two technicians are discussing the camshaft in a V8 engine. Technician A says to use an outside micrometer to measure the diameter of a camshaft journal. Technician B says a camshaft spins twice for every one revolution of the crankshaft. Who is correct?
A. Technician A
B. Technician B
C. Both A and B
D. Neither A or B
Answer A is correct. Use an outside micrometer to check camshaft journal diameter.
A vehicle is emitting black exhaust from its tailpipe under all driving conditions. This is because:
A. There is oil in the combustion chamber.
B. There is coolant in the combustion chamber.
C. There is too much fuel in the combustion chamber.
D. There is too much air in the combustion chamber.
Answer C is correct. Excess fuel in the combustion chamber results in black smoke.
The top compression ring groove of a piston has worn excessively, and the gap is found to be larger than specifications. The technician would MOST likely:
A. Use a tapered ring set to repair this piston.
B. Use oversized rings to repair this piston.
C. Use a ring groove cleaner to repair the grooves.
D. Replace the piston.
Answer D is correct. Replace the damaged piston.
During initial inspection the technician notices that there’s a strong sulfur odor emitting from the vehicle’s tailpipe. The customer states that the vehicle has been getting poor fuel mileage. The MOST likely cause of this condition is:
A. A lean fuel condition.
B. Leaking head gasket.
C. Worn piston rings.
D. A rich fuel condition.
Answer D is correct. A rich fuel condition will result in a sulfur smell coming from the vehicle's tailpipe.
A technician performs a battery capacity test on a vehicle that will not start. The test results in a reading of 9.1 volts at 70° F. Technician A says the battery has failed the capacity test. Technician B says battery voltage readings will increase as temperature decreases. Who is correct?
A. Technician A
B. Technician B
C. Both A and B
D. Neither A or B
Answer A is correct. If the capacity voltage goes below 9.6 volts at 70° F the battery has failed the capacity test.
A vehicle has heavy white smoke emitting from its tailpipe at all engine speeds. The cause of this problem is:
A. Worn piston rings.
B. A leaking head gasket.
C. Worn valve seals.
D. A leaking fuel injector.
Answer B is correct. A leaking head gasket results in a coolant leak from the jacket into the cylinder producing white/gray exhaust.
A vacuum gauge is connected to a port on the intake manifold of an engine with poor performance. The needle on the gauge fluctuates between 15 "hg and 20 "hg vacuum at idle. This vacuum gauge reading indicates:
A. A normal condition.
B. Late ignition or valve timing.
C. A sticking valve or misfire.
D. A restricted exhaust system.
Answer C is correct. A gauge that fluctuates between (15 "hg and 20 "hg) indicates a stuck valve or engine misfire.
Technician A says an engine's main bearing insert has a hole that must align with the matching bores oil supply hole. Technician B says that crankshaft bore alignment can be checked with a feeler gauge and a straightedge. Who is correct?
A. Technician A
B. Technician B
C. Both A and B
D. Neither A or B
Answer C is correct. Always make sure the two holes and all bores are in alignment when replacing the crankshaft bearing inserts.
A cylinder power balance test is being performed on a vehicle with sequential fuel injection. Two adjacent cylinders are under performing. Technician A says this could be due to a faulty head gasket. Technician B says this could be due to leaking secondary insulation. Who is correct?
A. Technician A
B. Technician B
C. Both A and B
D. Neither A or B
Answer C is correct. Both restricted fuel injectors and leaking secondary wires will reduce the cylinder's contribution.
Two technicians are discussing hydraulic lifter preload. Technician A says excessive preload will cause high manifold vacuum. Technician B says insufficient preload will cause excessive valve train noise. Who is correct?
A. Technician A
B. Technician B
C. Both A and B
D. Neither A or B
Answer B is correct. Insufficient lifter preloads will cause valve train noise.
A vehicle's cooling system is loosing coolant. There is corrosion found around the aluminum water pump. Which of these is MOST likely to cause this condition.
A. Stuck open thermostat.
B. Electrolysis.
C. Loose radiator cap.
D. Faulty head gasket.
Answer B is correct. Electrolysis causes corrosion of dissimilar metals in a cooling system. The weaker metal of the two (aluminum) will corrode.
A technician installs a radiator pressure tester on the radiator of a cold engine. After starting the engine the pressure quickly rises to 18 psi. Technician A says this is a normal condition. Technician B says the engine has a leaking cylinder head gasket. Who is correct?
A. Technician A
B. Technician B
C. Both A and B
D. Neither A or B
Answer B is correct. A leaking head gasket will force combustion into the coolant system causing an increase in system pressure.
Two Technicians are discussing a PCV system. Technician A says a stuck closed PCV valve could cause external oil leaks. Technician B says that the PCV system removes blowby gases from the engine case. Who is correct?
A. Technician A
B. Technician B
C. Both A and B
D. Neither A or B
Answer C is correct. The PCV system is a one-way system that allows blowby gas from the crankcase to flow into the intake manifold for recombustion. It helps keep the crankcase and engine oil clean.
An OHC engine has recently had the cylinder head replaced. The engine runs rough and stumbles. Technician A says this may be caused by incorrect valve lash adjustment. Technician B says that only in-block camshafts require valve lash adjustments. Who is correct?
A. Technician A
B. Technician B
C. Both A and B
D. Neither A or B
Answer A is correct. It is common to adjust the valves when tuning or after replacing the cylinder head.
Technician A says worn valve springs result in valve float at wide open throttle. Technician B says valve springs should be inspected for squareness with a square and a feeler gauge. Who is correct?
A. Technician A
B. Technician B
C. Both A and B
D. Neither A or B
Answer C is correct. Both technicians are correct.
Technician A says the valves in many interference engines open further into the combustion chamber that than those of a non-interference engine. Technician B says a broken timing belt in an interference engine can result in damage to the engine's valve train. Who is correct?
A. Technician A
B. Technician B
C. Both A and B
D. Neither A or B
Answer C is correct. The valve can strike the piston when out of time in an interference engine.
The spark plug is removed and shop air is introduced to the #1 cylinder while at TDC. Bubbles are seen in the radiator neck. The MOST likely cause of this condition is:
A. A bent intake valve.
B. Worn piston rings.
C. A burned exhaust valve.
D. A leaking head gasket.
Answer D is correct. Air is leaking from the cylinder, past the gasket, and into the coolant jacket. Air bubbles are now seen floating up to the radiator neck
A vehicle is emitting black smoke from its tailpipe, has poor fuel mileage and the torque converter is not engaging. Technician A says the ECT sensor's signal will effect TCC application. Technician B says the ECT sensor will affect the engine's fuel mixture. Who is correct?
A. Technician A
B. Technician B
C. Both A and B
D. Neither A or B
Answer C is correct. Both technicians are correct.
Technician A says a flex fan will increase its pitch at higher engine speeds. Technician B says a viscous fan clutch contains a silicon based fluid and should be checked for leaks. Who is correct?
A. Technician A
B. Technician B
C. Both A and B
D. Neither A or B
Answer B is correct. A viscous fan clutch contains a silicon based fluid.
A vehicle has a clogged catalytic converter. The LEAST likely cause of this is:
A. A rich fuel condition.
B. A leaking fuel injector.
C. A cracked intake manifold.
D. A fouled spark plug.
Answer C is correct. This is a LEAST LIKELY type question. A rich, not lean condition is likely to cause internal damage to a catalytic converter.
The reading on the micrometer indicates:
A. 6.05 mm
B. 6.00 mm
C. 5.50 mm D. 6.50 mm
Answer D is correct. The micrometers reading is 6.50 mm.
A technician is checking for piston ring groove clearance. The proper technique includes.
A. The old ring and a feeler gauge.
B. The new ring and a feeler gauge.
C. Only a feeler gauge.
D. No feeler gauge is required.
Answer B is correct. Clean the pistons in a cold tank and then clean the grooves with a ring groove cleaner before measuring.
A cylinder power balance test is being performed on a vehicle with sequential fuel injection. The number five cylinder's rpm drop is less than all of the others. Technician A says this could be the result of a restriction in the fuel injector. Technician B says this could be caused by leaking secondary insulation. Who is correct?
A. Technician A
B. Technician B
C. Both A and B
D. Neither A or B
Answer C is correct. Both restricted fuel injectors and leaking secondary wires will reduce the cylinder's contribution. Anything that would have an affect on the cylinder's power. It could be mechanical like a faulty valve, possibly the ignition, or the fuel mixture affecting this cylinder's power output.
A turbocharger wastegate is sticking. Technician A says a stuck open wastegate will result in overboost. Technician B says a stuck closed wastegate will result in an underboost condition. Who is correct?
A. Technician A
B. Technician B
C. Both A and B
D. Neither A or B
Answer D is correct. Neither technician is correct.
An engine has excessive crankshaft endplay. Which of the following is MOST likely causing this condition?
A. Camshaft bearings
B. Thrust bearings
C. Crankshaft main bearings
D. Rod bearings
Answer B is correct. The thickness of the thrust bearing indicates crankshaft endplay.
A wet compression test is being performed on a four cylinder engine. The number two cylinder's compression is below specifications and remains the same after injecting oil. This result indicates:
A. Worn piston rings.
B. A faulty valve.
C. A hole in the piston.
D. Excessive carbon buildup on the piston's dome.
Answer B is correct. If there is no change in compression after adding oil, the cylinder has a faulty head gasket or valve.
A vehicle has blue colored exhaust. Technician A says this may be caused by weak piston rings. Technician B says this may be caused by a leaking fuel injector. Who is correct?
A. Technician A
B. Technician B
C. Both A and B
D. Neither A or B
Answer A is correct. Oil is burning in the combustion chamber causing blue colored exhaust.
Technician A says to remove the ridge on the engine block before removing the pistons. Technician B says a block's ridge will damage the new piston rings during installation. Who is correct?
A. Technician A
B. Technician B
C. Both A and B
D. Neither A or B
Answer C is correct. Remove the damaging ridge with a ridge reamer before removing pistons. This also prevents damage to the new piston rings when it comes time to reinstall the pistons.
A vehicle briefly blows blue/gray smoke from the tailpipe when it's first started in the morning. The MOST likely cause of this condition is a:
A. Worn piston ring.
B. Lean fuel condition.
C. Leaking fuel injector.
D. Leaking valve seal.
Answer D is correct. A leaking valve seal will cause oil to leak into the cylinder's chamber over time, usually overnight.
Two technicians are discussing an engine with a collapsed radiator hose. Technician A says this is caused by a faulty radiator cap. Technician B says this is caused by insufficient coolant level. Who is correct?
A. Technician A
B. Technician B
C. Both A and B
D. Neither A or B
Answer A is correct. The vacuum valve in the radiator cap is sticking. A radiator cap acts as a two way valve that allows coolant to flow to and from the coolant reservoir.
A vehicle is overheating, but returns to normal at idle. Both of the engine’s electric cooling fans are functioning correctly. Technician A says this could be caused by an internal restriction in the radiator. Technician B says an infrared thermometer is used to diagnose this problem. Who is correct?
A. Technician A
B. Technician B
C. Both A and B
D. Neither A or B
Answer C is correct. Both technicians are correct.
A metallic knocking sound is heard behind an engine's harmonic balancer. An oil pressure test indicates oil pressure is below specifications. Technician A says the engine's main bearing inserts should be inspected for wear. Technician B says a worn thin crankshaft thrust bearing will cause this condition. Who is correct?
A. Technician A
B. Technician B
C. Both A and B
D. Neither A or B
Answer C is correct. Both technicians are correct.
A vehicle vibrates only when placed in reverse. The MOST likely cause of this condition is:
A. Crossed ignition wires.
B. A faulty fuel injector.
C. A faulty balance shaft.
D. A broken engine mount.
Answer D is correct. A worn or broken engine mount would result in a vibration that is more pronounced in reverse or in drive.
Two technicians are discussing a turbocharged engine. Technician A says the wastegate is a component used to control boost pressure. Technician B says when opened, the wastegate diverts exhaust gas from the turbine wheel. Who is correct?
A. Technician A
B. Technician B
C. Both A and B
D. Neither A or B
Answer C is correct. Both technicians are correct.
Technician A says that torque to yield bolts can always be reused. Technician B says that torque to yield bolts can be reused as long as they are cleaned and oiled before they are reinstalled and torqued. Who is correct?
A. Technician A
B. Technician B
C. Both A and B
D. Neither A or B
Answer D is correct. Neither technician is correct.
A cylinder leak-down test is being performed on an engine.
Technician A says that the engine should be cold.
Technician B says that the piston should be at TDC on the compression stroke.
Who is right?
(B)
A vehicle with a 4-cylinder engine is towed into a shop with a no crank complaint. The amperage meter in the illustration is connected to the circuit and the key is turned to the START position. Which of these could be the cause of the reading shown?
(A) A weak battery
(B) A poor ground connection
(C) A seized engine
(D) An open starter solenoid
c
An engine is being diagnosed for a knocking noise that is heard when the engine is cold, but not heard at operating temperature. This could be caused by a:
(D)
The results of dry and wet cranking compression tests are the same on a cylinder with low compression.
Technician A says that a leaking valve seat could be the cause.
Technician B says that a broken compression ring could be the cause.
(A)
A customer is complaining that the vehicle's engine uses too much oil. No external leaks are found. This could be caused by a worn:
(A)
During a diagnosis the technician observes that engine vacuum is 12 in. Hg. with the engine warm and idling. Which of these could be the cause?
(A)
This question is not like the other questions on the test. It uses the word EXCEPT. Read the question carefully before choosing your answer.
A technician is using a scan tool to perform a cylinder power balance test on a V-6 engine that has stored DTCs of "Cylinder #2 Misfire Detected" and "Cylinder #6 Misfire Detected". Cylinders #2 and #6 have no RPM drop during the test. Compression and cylinder leakage tests were performed and the results are shown. Any of these could be the cause EXCEPT:
(A) open spark plug wires.
(B) a leaking intake gasket.
(C) plugged fuel injectors.
(D) burned exhaust valves.
D
The customer complains that the engine is sluggish when accelerating. During testing, the vacuum gauge reads 20 in. Hg. at idle with the transmission in PARK. During a test drive, vacuum measures near 0 in. Hg. at wide open throttle. During light cruise speed at 2000 RPM, the vacuum measures a steady 12 in. Hg. Which of these could be the cause?
(D)
Which of these is best to use when cleaning a gasket surface on an aluminum cylinder head?
(A)
What procedure is being performed in the illustration?
(C)
The installed height of a valve spring is greater than specified.
Technician A says that a worn valve seat could be the cause.
Technician B says that a weak valve spring could be the cause.
Who is right?
(A)
A new overhead camshaft will not rotate by hand when installed in a cylinder head. Which of these could be the cause?
(D)
Which of these is being measured in the illustration shown?
(C)
Technician A says that anaerobic sealer should be used on both sides of a rubberized cork gasket.
Technician B says that multi-layered steel (MLS) head gaskets can be reused.
Who is right?
(D)
This question is not like the other questions on the test. It uses the word EXCEPT. Read the question carefully before choosing your answer.
Any of these are true of cracked cap connecting rods EXCEPT:
(B)
After honing the cylinders in an engine block, the technician should do a final cleaning with:
(B)
An OBD II-equipped vehicle has a noticeable vibration at all times when the engine is running. There are no trouble codes set. Which of these could be the cause?
(C)
Technician A says that torque-to-yield bolts are designed to stretch when they are tightened.
Technician B says that the torque specification of torque-to-yield bolts should be increased by 10% if they are reused.
Who is right?
(A)
A customer complains that the engine overheats at idle but not at highway speeds. Which of these could be the cause?
(A)
Extensive engine bearing damage has been observed during disassembly.
Technician A says that an internal engine coolant leak could be the cause.
Technician B says that a stuck-closed oil pressure relief valve could be the cause.
Who is right?
(A)
While test driving a vehicle, it is noted that the oil pressure light illuminates at idle, but goes out immediately with the slightest increase in RPM. Which of these could be the cause?
(B)
After a cooling system flush was performed, there is very little heat inside the passenger compartment.
Technician A says that air trapped in the engine cooling system could be the cause.
Technician B says that the use of an incorrect coolant mixture could be the cause.
Who is right?
(A)
Technician A says that the lubrication supply lines should be inspected for debris when replacing a turbocharger.
Technician B says that the engine oil should be changed when replacing a turbocharger.
Who is right?
(C)
An engine is being examined for an external oil leak complaint. Which of these could be the cause?
(D)
The scan data shown was observed during diagnosis of a vehicle for an illuminated malfunction indicator lamp (MIL) and a stored "System Too Lean - Bank 1" DTC. Which of these could be the cause?
(C)
1. Engine crack repair is being discussed. Technician A says metal pinning is an accepted method of cracked cylinder head repair. Technician B says metal pinning is an accepted method of cracked engine block repair. Who is correct?
Technician A
Technician B
Both A and B
Neither A or B
C
2. Which of these is LEAST likely to cause low oil pressure in an engine.
A faulty oil pressure valve.
A worn crankshaft bearings.
A worn camshaft bearings.
Worn valve guides
D
3. Technician A says valve spring installed height is measured from the outer edge of the valve spring retainer to the pocket in the cylinder head. Technician B says that too thin of a valve margin will not effect its operating temperature. Who is correct?
Technician A
Technician B
Both A and B
Neither A or B
A
Technician A says that magnetic particle detection is an acceptable method to detect cracks in aluminum castings. Technician B says a special dye is used to detect cracks in aluminum castings. Who is correct?
Technician A
Technician B
Both A and B
Neither A or B
B
5. Technician A says that minor scoring on the surface of a flywheel can be removed. Technician B says if the transmission flexplate's ring gear shows excessive wear or cracking it must be replaced. Who is correct?
Technician A
Technician B
Both A and B
Neither A or B
C
6. Two technicians are discussing the camshaft in a V8 engine. Technician A says to use an outside micrometer to measure the diameter of a camshaft journal. Technician B says a camshaft spins twice for every one revolution of the crankshaft. Who is correct?
Technician A
Technician B
Both A and B
Neither A or B
A
7. A vehicle is emitting black exhaust from its tailpipe under all driving conditions. This is because:
There is oil in the combustion chamber.
There is coolant in the combustion chamber.
There is too much fuel in the combustion chamber.
There is too much air in the combustion chamber.
C
8. The top compression ring groove of piston is worn excessively and the gap is found to be larger than specifications. The technician would MOST likely:
Use a tapered ring set to repair this piston.
Use oversized rings to repair this piston.
Use a ring groove cleaner to repair the grooves.
Replace the piston.
D
9. During initial inspection the technician notices that there’s a strong sulfur odor emitting from the vehicle’s tailpipe. The customer states that the vehicle has been getting poor fuel mileage. The MOST likely cause of this condition is:
A lean fuel condition.
Leaking head gasket.
Worn piston rings.
A rich fuel condition.
D
10. A technician performs a battery capacity test on a vehicle that will not start. The test results in a reading of 9.1 volts at 70° F. Technician A says the battery has failed the capacity test. Technician B says battery voltage readings will increase as temperature decreases. Who is correct?
Technician A
Technician B
Both A and B
Neither A or B
A
11. A vehicle has heavy white smoke emitting from its tailpipe at all engine speeds. The cause of this problem is:
Worn piston rings.
A leaking head gasket.
Worn valve seals.
A leaking fuel injector.
B
12. A vacuum gauge is connected to a port on the intake manifold of an engine with poor performance. The needle on the gauge fluctuates between 15 "hg and 20 "hg vacuum at idle. This vacuum gauge reading indicates:
A normal condition.
Late ignition or valve timing.
A sticking valve or misfire.
A restricted exhaust system.
C
13. Technician A says an engine's main bearing insert has a hole that must align with the matching bores oil supply hole. Technician B says that crankshaft bore alignment can be checked with a feeler gauge and a straightedge. Who is correct?
Technician A
Technician B
Both A and B
Neither A or B
C
14. A cylinder power balance test is being performed on a vehicle with sequential fuel injection. Two adjacent cylinders are under performing. Technician A says this could be due to a faulty head gasket. Technician B says this could be due to leaking secondary insulation. Who is correct?
Technician A
Technician B
Both A and B
Neither A or B
C
15. Two technicians are discussing hydraulic lifter preload. Technician A says excessive preload will cause high manifold vacuum. Technician B says insufficient preload will cause excessive valve train noise. Who is correct?
Technician A
Technician B
Both A and B
Neither A or B
B
16. A vehicle's cooling system is loosing coolant. There is corrosion found around the aluminum water pump. Which of these is MOST likely to cause this condition.
Stuck open thermostat.
Electrolysis.
Loose radiator cap.
Faulty head gasket.
B
17. A technician installs a radiator pressure tester on the radiator of a cold engine. After starting the engine the pressure quickly rises to 18 psi. Technician A says this is a normal condition. Technician B says the engine has a leaking cylinder head gasket. Who is correct?
Technician A
Technician B
Both A and B
Neither A or B
B
18. Two Technicians are discussing a PCV system. Technician A says a stuck closed PCV valve could cause external oil leaks. Technician B says that the PCV system removes blowby gases from the engine case. Who is correct?
Technician A
Technician B
Both A and B
Neither A or B
C
19. An OHC engine has recently had the cylinder head replaced. The engine runs rough and stumbles. Technician A says this may be caused by incorrect valve lash adjustment. Technician B says that only in-block camshafts require valve lash adjustments. Who is correct?
Technician A
Technician B
Both A and B
Neither A or B
A
20. Technician A says worn valve springs result in valve float at wide open throttle. Technician B says valve springs should be inspected for squareness with a square and a feeler gauge. Who is correct?
Technician A
Technician B
Both A and B
Neither A or B
